Answer: B) False
The statement is false because dissolution is not limited to liquid substances entering a solvent—it describes the process where a solute (which can be solid, liquid, or gas) dissolves into a solvent to form a solution.
Fundamental Definition of Dissolution
The provided statement incorrectly restricts dissolution to "liquid substances" only. In pharmaceutical and chemical sciences, dissolution is defined more broadly:
- Dissolution involves any solute (solid, liquid, or gas) dispersing at the molecular or ionic level into a solvent to create a homogeneous solution 1
- The term "solution" specifically indicates that materials are dissolved at the molecular level, distinct from "suspension" or "dispersion" where particles remain undissolved 1
Critical Terminology Distinctions
The scientific literature emphasizes precise terminology to avoid misinterpretation:
- "True" dissolution refers to the breakdown of substances into their constituent ions or molecules, not merely physical dispersion 1
- Materials in suspension or dispersion are not dissolved—they remain as particles in the medium, which is fundamentally different from dissolution 1
- For example, nanoparticle suspensions have been erroneously called "dissolved" when they are actually "dispersed" or "suspended," highlighting the importance of correct terminology 1
Common Examples Contradicting the Statement
The most common pharmaceutical dissolution scenarios involve solid drugs dissolving in liquid media:
- Drug nanocrystals and nano-cocrystals undergo dissolution from solid state into aqueous solutions 1
- Poorly soluble solid compounds like glibenclamide dissolve in dissolution media 2
- Ibuprofen tablets (solid dosage forms) dissolve in gastrointestinal fluids 3
Practical Implications
In pharmaceutical quality control and drug development:
- Dissolution testing primarily involves solid dosage forms (tablets, capsules, powders) dissolving in liquid media 4, 5
- The dissolution process is characterized by the solute transitioning from solid state to dissolved molecular/ionic state in solution 1
- Regulatory dissolution methods focus on solid drug products, not liquid-to-liquid mixing 4
The original statement's restriction to "liquid substance" fundamentally misrepresents the dissolution process, which most commonly and importantly involves solid substances dissolving in solvents.